Adverse effects of analgesics commonly used by older adults with osteoarthritis: focus on non-opioid and opioid analgesics

Abstract

Background: Osteoarthritis (OA) is the most common cause of disability in older adults, and although analgesic use can be helpful, it can also result in adverse drug events.

Objective: To review the recent literature to describe potential adverse drug events associated with analgesics commonly used by older adults with OA.

Methods: To identify articles for this review, a systematic search of the English-language literature from January 2001 to June 2012 was conducted using PubMed, MEDLINE, EBSCO, and the Cochrane Database of Systematic Reviews for publications related to the medical management of OA. Search terms used were "analgesics," "acetaminophen," "nonsteroidal anti-inflammatory drugs" (NSAIDs), "opioids," "pharmacokinetics," "pharmacodynamics," and "adverse drug events." The search was restricted to those articles that concerned humans aged ≥65 years. A manual search of the reference lists from identified articles and the authors' article files, book chapters, and recent reviews was conducted to identify additional articles. From these, the authors identified those studies that examined analgesic use in older adults.

Results: There are limited data to suggest that non-frail elders are more likely than their younger counterparts to develop acetaminophen-induced hepatotoxicity. However, decreased hepatic phase II metabolism in frail elders may result in increased risk of hepatotoxicity. It is now well established that older adults are at higher risk of NSAID-induced gastrointestinal toxicity and renal insufficiency. Insofar as opioids, the data that suggest an increased risk of falls, fractures, or delirium need to be tempered by the potential risk of inadequately treating severe chronic OA-related pain.

Conclusions: Acetaminophen is the mainstay frontline analgesic for treating OA-related pain in older adults. NSAIDs should be limited to short-term use only, and for moderate to severe OA-related pain, opioids may be preferable in individuals without substance abuse or dependence issues.